1. Field of the Invention
This invention relates to an improvement on a camera having a magnetic head arranged to record and reproduce, as magnetic signals, information of varied kinds in and from magnetic recording parts of a film.
2. Description of the Related Art
A camera of the kind arranged in such a manner that, when the camera is loaded again with a film cartridge which has been taken out before all available frames of it are exposed with a magnetic signal recorded at each exposed frame by a magnetic head, a discrimination is made for each frame between exposed and unexposed states according to the presence or absence of the magnetic signal and then the leading part of each unexposed frame thus found is located, has been disclosed in Japanese Laid-Open Patent Application No. HEI 4-68329. Another camera which has been disclosed in Japanese Laid-Open Patent Application No. HEI 5-158165 is arranged to retract a magnetic head from a film surface when magnetic signal reproduction is not necessary. Further, a camera which is arranged to reproduce, in rewinding the film, a magnetic signal for the purpose of checking data recorded at the time of film winding has been disclosed in Japanese Patent Application No. HEI 5-183236.
However, the first example of the prior art mentioned above is arranged to make a discrimination between exposed and unexposed states only in winding the film. Therefore, once it becomes impossible to obtain a reproduced signal for a frame due to some accident, all frames thereafter might be decided to be unexposed.
In the case of the second example of the prior art, the magnetic head is arranged to be retracted from the film surface only for a film which has not yet been used.
In the third example of the prior art, no heed is given to the necessity of a checking action on a film taken out before all its available frames are used.